我正在使用recyclerView
在listitems
中显示我的navigation drawer
。我已经实现了onclickListener
,但是当项目是activity
时,我一直坚持如何打开其他clicked
。到目前为止,我所有的项目都按代码进行项目单击,以显示带有toast
的item position
。
我会很感激的。
AdapterClass.java
public class AdapterClass extends RecyclerView.Adapter<AdapterClass.MyViewHolder> {
private LayoutInflater inflater;
private Context context;
List<Information>data= Collections.emptyList();
public AdapterClass(Context context,List<Information>data){
this.context=context;
inflater= LayoutInflater.from(context);
this.data=data;
}
@Override
public MyViewHolder onCreateViewHolder(ViewGroup parent, int viewType) {
View view= inflater.inflate(R.layout.custom_row,parent,false);
MyViewHolder holder=new MyViewHolder(view);
return holder;
}
@Override
public void onBindViewHolder(MyViewHolder holder, int position) {
Information current=data.get(position);
holder.title.setText(current.title);
holder.icon.setImageResource(current.iconId);
}
@Override
public int getItemCount() {
return data.size();
}
class MyViewHolder extends RecyclerView.ViewHolder implements View.OnClickListener{
TextView title;
ImageView icon;
public MyViewHolder(View itemView) {
super(itemView);
title=(TextView)itemView.findViewById(R.id.listText);
icon=(ImageView)itemView.findViewById(R.id.listIcon);
itemView.setClickable(true);
itemView.setOnClickListener(this);
}
@Override
public void onClick(View v) {
Toast.makeText(context,"The Item Clicked is: "+getPosition(),Toast.LENGTH_SHORT).show();
}
};
}
Log cat error after implementing Konrad's solution
02-27 15:24:52.833: D/AndroidRuntime(1630): --------- beginning of crash
02-27 15:24:52.834: E/AndroidRuntime(1630): FATAL EXCEPTION: main
02-27 15:24:52.834: E/AndroidRuntime(1630): Process: com.snappy.stevekamau.snappy, PID: 1630
02-27 15:24:52.834: E/AndroidRuntime(1630): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.snappy.stevekamau.snappy/com.snappy.stevekamau.snappy.YourActivity}: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.CharSequence android.support.v7.widget.Toolbar.getTitle()' on a null object reference
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2298)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2360)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread.access$800(ActivityThread.java:144)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1278)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.os.Handler.dispatchMessage(Handler.java:102)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.os.Looper.loop(Looper.java:135)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread.main(ActivityThread.java:5221)
02-27 15:24:52.834: E/AndroidRuntime(1630): at java.lang.reflect.Method.invoke(Native Method)
02-27 15:24:52.834: E/AndroidRuntime(1630): at java.lang.reflect.Method.invoke(Method.java:372)
02-27 15:24:52.834: E/AndroidRuntime(1630): at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:899)
02-27 15:24:52.834: E/AndroidRuntime(1630): at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:694)
02-27 15:24:52.834: E/AndroidRuntime(1630): Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'java.lang.CharSequence android.support.v7.widget.Toolbar.getTitle()' on a null object reference
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.support.v7.internal.widget.ToolbarWidgetWrapper.<init>(ToolbarWidgetWrapper.java:95)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.support.v7.internal.widget.ToolbarWidgetWrapper.<init>(ToolbarWidgetWrapper.java:88)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.support.v7.internal.app.ToolbarActionBar.<init>(ToolbarActionBar.java:84)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.support.v7.app.ActionBarActivityDelegateBase.setSupportActionBar(ActionBarActivityDelegateBase.java:175)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.support.v7.app.ActionBarActivity.setSupportActionBar(ActionBarActivity.java:92)
02-27 15:24:52.834: E/AndroidRuntime(1630): at com.snappy.stevekamau.snappy.YourActivity.onCreate(YourActivity.java:18)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.Activity.performCreate(Activity.java:5933)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1105)
02-27 15:24:52.834: E/AndroidRuntime(1630): at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2251)
02-27 15:24:52.834: E/AndroidRuntime(1630): ... 10 more
02-27 15:24:52.839: W/ActivityManager(464): Force finishing activity com.snappy.stevekamau.snappy/.YourActivity
02-27 15:24:52.841: W/ActivityManager(464): Force finishing activity com.snappy.stevekamau.snappy/.MainActivity
最佳答案
您可以(但不必这样做,因为ViewHolder
类不是静态的)创建字段上下文,如下所示:
private final Context context;
public MyViewHolder(View itemView) {
super(itemView);
context = itemView.getContext();
...
}
并在
onClick
方法上仅调用sth,如下所示:@Override
public void onClick(View v) {
final Intent intent;
switch (getAdapterPostion()){
case 0:
intent = new Intent(context, FirstActivity.class);
break;
case 1:
intent = new Intent(context, SecondActivity.class);
break;
...
default:
intent = new Intent(context, DefaultActivity.class);
break;
}
context.startActivity(intent);
}
或者
@Override
public void onClick(View v) {
final Intent intent;
if (getAdapterPosition() == sth){
intent = new Intent(context, OneActivity.class);
} else if (getPosition() == sth2){
intent = new Intent(context, SecondActivity.class);
} else {
intent = new Intent(context, DifferentActivity.class);
}
context.startActivity(intent);
}